Child have pain in stomach. No medication till now. What to do for the pain?

Hi I'm 12 and I've had these pains in my stomach sometimes in the upper area and sometimes in the lower I have never had my period but I assume that I'm going to get it soon the pains go on and off like just 5 minutes ago they were in my lower abdomen and now their higher on the right side under my rib cage and I'm not sure if I should feel concerned

Pain in different areas and different times may be intestinal colic...
There is liver and gall bladder under the rib cage on the right side...
Lower down, it may from ureter, bladder, ovary, uterus and so on...
It is better to get examined and investigated - urine, stool, blood tests and ultrasound are generally done as a routine / to exclude most routine problems...

For how long have you had these pains? Did they start today? The pain is better or worse when you eat? It could be menstrual cramps or a stomach condition. Per your description it should not be something serious. Please answer my questions so I can assess the situation in a better way. I hope you get better soon.